Midsummer 2017: teenage mum Tallulah heads out on a date, leaving her baby son at home with her mother, Kim. At 11pm she sends her mum a text message. At 4.30am Kim awakens to discover that Tallulah has not come home Friends tell her that Tallulah was last seen heading to a pool party at a house in the woods nearby called Dark Place Tallulah never returns. 2018: walking in the woods behind the boarding school where her boyfriend has just started as a head-teacher, Sophie sees a sign nailed to a fence. A sign that says: DIG HERE...